In diffusion-weighted MRI, eddy current effects
notoriously result in geometrical image distortions. This problem is usually
approached by fine-calibration of the scanner gradient system. We present a
generic way of addressing this problem by deliberately tolerating a certain
degree of field deviations in terms of eddy currents, gradient delays and field
drifts and rather monitor the actual magnetic field during each scan. The field
evolution thereby obtained is used for distortion correction of in-vivo
DWI data that was acquired in the absence of hardware eddy current
compensation.